Roller bearings are bearings which carry a load by placing rolling elements between two bearing rings called races. The rolling elements can be balls, cylindrical rollers, spherical rollers, tapered rollers, or needle rollers. The rolling elements are usually caged to prevent the elements from rubbing against each other.
Spherical roller bearings have been in use for nearly 100 years. The basic design consists of an inner ring with two raceways inclined at an angle to the bearing axis, an outer ring with a common spherical raceway, spherical rollers, and roller cages. The so-called spherical rollers are actually barrel-shaped cylinders, i.e. cylindrical rollers having a convex side profile. More recently, a single row spherical roller bearing called a CARB (Compact self-Aligning Roller Bearing) has been available. FIG. 1 illustrates an example of a CARB, which includes a single row having radial contacts between the convex rollers and the spherical profiles of the inner and outer races. The outer ring race is a toroidal raceway with a profile radius extending beyond the centre of the bearing. The convex rollers are symmetrical, barrel-shaped cylinders. The inner race ring is shaped accordingly. Each roller is caged. Such roller bearings may allow axial displacement up to ˜10% of the bearing width and can accommodate up to 0.5° of misalignment. Both angular and axial self-alignment is provided.
The present invention aims to provide an improved roller bearing and related method of assembly.